喷淋鼓泡塔内氨水对烟气中As2O3的吸收特性  

Absorption characteristics of As2O3 from flue gas by ammonia in spray-and-bubble column

作　　者：魏永久 张月[1] 郭雨生 王春波[1] 白涛 WEI Yongjiu;ZHANG Yue;GUO Yusheng;WANG Chunbo;BAI Tao(Department of Energy Power&Mechanical Engineering,North China Electric Power University,Baoding 071003,Hebei,China;Department of Power Engineering,Shanxi University,Taiyuan 030013,Shanxi,China)

机构地区：[1]华北电力大学能源动力与机械工程学院,河北保定071003 [2]山西大学动力工程系,山西太原030013

出　　处：《化工进展》2020年第3期834-841,共8页Chemical Industry and Engineering Progress

基　　金：国家重点研发计划(2016YFB0600704);中央高校基本科研业务费项目(2019MS093,2018ZD03);山西省重点研发(社会发展)计划(201803D31027)。

摘　　要：喷淋鼓泡塔内的反应是典型的气液两相流,为研究喷淋鼓泡内氨水对烟气中As2O3吸收特性,探索新型喷淋鼓泡技术的污染物一体化控制潜力,以空气和SO2为模拟烟气,利用喷淋鼓泡吸收塔研究了液气比、浸液深度、氨水质量浓度、SO2质量浓度对氨水吸收气相As2O3的影响。研究表明:氨水对As2O3的吸收效率随液气比增加先增大后趋于平缓;浸液深度增大,氨水吸收As2O3的效率降低;As2O3与氨水中OH-作用生成的AsO33-溶于氨水实现氨水对As2O3的吸收,氨水吸收As2O3的效率随氨水质量浓度的增大先上升后下降;碱性环境下,SO2与NH3作用生成SO32-的水解增加了溶液中OH-,促进了氨水对As2O3的吸收,又因SO32-水解产生HSO3-电离出H+对部分OH-中和以及NH3挥发等因素,促进作用表现为吸收效率随SO2质量浓度的增加先上升后下降。在氨水质量浓度为0.07%、SO2质量浓度为525mg/m^3、液气比10L/m^3、浸液深度5cm时吸收效率达到最大82%。The reaction in the spray-and-bubble column is a typical gas-liquid flow. In order to study the absorption characteristics of As2O3 in the flue gas by ammonia in spray-and-bubble column and explore the potential of the integrated control of pollutants by the novel spray-and-bubble technology, the spray-and-bubble column was employed to investigate the synergistic removal of As2O3 from flue gas using air and SO2 as the simulated flue gas. Factors such as liquid-gas ratio, bubbling pipe depth,aqueous ammonia concentration and SO2 concentration have been studied. Results showed that the As2O3 adsorption efficiency increases generally and then tends to be gentle with the liquid-gas ratio rising. The increase of immersion depth leads to the gradual decrease of absorption efficiency. The absorption efficiency of AsO33- formed by the interaction between As2O3 and OH-in ammonia dissolves in ammonia to achieve As2O3 absorption. Under alkaline environment, the hydrolysis of SO32- generated by the reaction between SO2 and NH3 increases the OH-in the solution to promote the absorption of ammonia to gas phase As2O3. The promotion effect first increases and then decreases with the increase of SO2 concentration due to factors such as the neutralization of some of the OH-by H+ in the NH4 HSO3 and volatilization of NH3.The absorption efficiency reaches the maximum of 82% when liquid-gas ratio is 10 L/m^3, immersion depth of 5 cm, ammonia concentration of 0.07% and SO2 concentration of 525 mg/m^3.

关 键 词：气液两相流 喷淋鼓泡 氨水 吸收 As2O3脱除 

分 类 号：TK221[动力工程及工程热物理—动力机械及工程]